This concerns a printed and embossed material, suitable for use as a floor covering, and a method and apparatus for making it in a continuous process. More particularly, it concerns a multilayered material combining a base layer, a printed layer and a wear resistant layer, which is embossed in register with the print.
Reverse printed laminates have been made by laminating separate sheets of calendered base material and a preprinted plastic film. In continuous processes, the printed designs have been limited to random prints because of the difficulty of maintaining the desired dimensions in the preprinted plastic film, in the laminate and in some cases in the base material. The plastic film tends to stretch when it is being printed and subsequently dried. Since it is necessary to apply tension to the printed film during lamination in order to eliminate trapped air and wrinkles, the printed design can also be distorted during lamination.
Alternatively, tiles can be formed in batch processes with designs that are in register to the cut tile by laminating preprinted plastic sheets of silk screen designs to sheets of a suitable base material. The tiles can then be hand clicked from the sheets. The high cost of such a batch process makes in-register printed tile quite expensive and limits its acceptance.
An additional complication is imposed by the desirability of providing a textured surface by embossing the tile. In the prior art the embossing step can be another cause of distortion. As a result, embossing in register with a printed design has previously been restricted to embossing of a plastic surface layer that is integral with a nonplastic stable substrate such as asbestos or asphalt-saturated felt. Attempts to emboss unsupported plastic layers in register with a printed design have been unsuccessful because the plastic is easily distorted when moving it at the elevated temperatures necessary for embossing.